Fine friend flipped, in a panic (4)
I believe the answer is:
flap
'a panic' is the definition.
(I've seen this before)
'fine friend flipped' is the wordplay.
'fine' becomes 'f' (abbreviation).
'friend' becomes 'pal' (pal is a kind of friend).
'flipped' is a reversal indicator.
'pal' in reverse letter order is 'lap'.
'f'+'lap'='FLAP'
'in' is the link.
(Other definitions for flap that I've seen before include "Move like a bird or get into a tizzy" , "Use wings; be agitated" , "Agitated state; tab" , "Minor panic; tab" , "Flutter" .)